Wimbledon weekend wrap-up

Juan Martin Del Potro of Argentina lays on the court after slipping over and crashing into the umpires chair during his Men's singles match against Grega Zemlja of Slovenia at the All England Lawn Tennis Championships in Wimbledon, London, Saturday, June 29, 2013. (AP Photo/Kirsty Wigglesworth)

Mikhail Youzhny of Russia reacts after winning a point against Viktor Troicki of Serbia in their Men's singles match at the All England Lawn Tennis Championships in Wimbledon, London, Saturday, June 29, 2013. (AP Photo/Kirsty Wigglesworth)

Petra Kvitova of the Czech Republic celebrates after beating Ekaterina Makarova of Russia in their Women's singles match at the All England Lawn Tennis Championships in Wimbledon, London, Saturday, June 29, 2013. (AP Photo/Anja Niedringhaus)

Serena Williams of the United States reacts after winning a point as she plays Kimiko Date-Krumm of Japan during their Women's singles match at the All England Lawn Tennis Championships in Wimbledon, London, Saturday, June 29, 2013. (AP Photo/Anja Niedringhaus)

Sabine Lisicki of Germany serves to Samantha Stosur of Australia during their Women's singles match at the All England Lawn Tennis Championships in Wimbledon, London, Saturday, June 29, 2013. (AP Photo/Sang Tan)

Sloane Stephens of the United States plays a shot to Petra Cetkovska of the Czech Republic in their Women's singles match at the All England Lawn Tennis Championships in Wimbledon, London, Saturday, June 29, 2013. (AP Photo/Alastair Grant)

Serena Williams of the United States smiles after beating Kimiko Date-Krumm of Japan in a Women's singles match at the All England Lawn Tennis Championships in Wimbledon, London, Saturday, June 29, 2013. (AP Photo/Sang Tan)

Kenny De Schepper of France plays a return to Juan Monaco of Argentina during their Men's singles match at the All England Lawn Tennis Championships in Wimbledon, London, Saturday, June 29, 2013. (AP Photo/Alastair Grant)

Madison Keys of United States smashes the ball as she plays Agnieszka Radwanska of Poland in a Women's singles match at the All England Lawn Tennis Championships in Wimbledon, London, Saturday, June 29, 2013. (AP Photo/Alastair Grant)

Lukasz Kubot of Poland returns to Benoit Paire of France during their Men's singles match at the All England Lawn Tennis Championships in Wimbledon, London, Saturday, June 29, 2013. (AP Photo/Kirsty Wigglesworth)

Britain's Andy Murray of Britain waves as he takes his seat on Centre Court at the All England Lawn Tennis Championships in Wimbledon, London, Saturday, June 29, 2013. (AP Photo/Sang Tan)

Serena Williams of the United States reacts after winning a point as she plays Kimiko Date-Krumm of Japan during their Women's singles match at the All England Lawn Tennis Championships in Wimbledon, London, Saturday, June 29, 2013. (AP Photo/Sang Tan)

David Ferrer of Spain gets treatment on his foot as he plays Alexandr Dolgopolov of Ukraine in their Men's singles match at the All England Lawn Tennis Championships in Wimbledon, London, Saturday, June 29, 2013. (AP Photo/Anja Niedringhaus)

Juan Martin Del Potro of Argentina receives treatment after crashing into the umpires chair during his Men's singles match against Grega Zemlja of Slovenia at the All England Lawn Tennis Championships in Wimbledon, London, Saturday, June 29, 2013. (AP Photo/Kirsty Wigglesworth)

Petra Cetkovska of the Czech Republic slips on the grass as she plays Sloane Stephens of the United States in their Women's singles match at the All England Lawn Tennis Championships in Wimbledon, London, Saturday, June 29, 2013. (AP Photo/Alastair Grant)

Marina Erakovic of New Zealand returns to Laura Robson of Britain during their Women's singles match at the All England Lawn Tennis Championships in Wimbledon, London, Saturday, June 29, 2013. (AP Photo/Kirsty Wigglesworth)

Madison Keys of United States returns the ball as she plays Agnieszka Radwanska of Poland in a Women's singles match at the All England Lawn Tennis Championships in Wimbledon, London, Saturday, June 29, 2013. (AP Photo/Alastair Grant)

Alexandr Dolgopolov of Ukraine returns to David Ferrer of Spain in their Men's singles match at the All England Lawn Tennis Championships in Wimbledon, London, Saturday, June 29, 2013. (AP Photo/Anja Niedringhaus)

Kimiko Date-Krumm of Japan returns to Serena Williams of the United States during their Women's singles match at the All England Lawn Tennis Championships in Wimbledon, London, Saturday, June 29, 2013. (AP Photo/Anja Niedringhaus)

Serena Williams of the United States plays a return to Kimiko Date-Krumm of Japan during their Women's singles match at the All England Lawn Tennis Championships in Wimbledon, London, Saturday, June 29, 2013. (AP Photo/Anja Niedringhaus)